When international peace is at stake, the United Nations Security Council has likely already debated a resolution on the issue. But a veto can stall meaningful action.Since 2005, Russia, China and the U.S. have exercised that power. The power of veto is exclusive to the council’s permanent members, which also include the U.K. and France. From sanctions on Iran to a peacekeeping mission in Bosnia, the Security Council has the tools to hold countries accountable but a veto can paralyze it.